All I'm askin is, is it kosher for me to be a Satanist and a lover of Norse mythology. I mean can I get tattoos and such of vikings and still be considered a practicing Satanist.
No, sorry - viking tattoos are reserved for scandinavian Satanists
... just kidding. I think Wolf Landon already answered your question really.
I'd like to add one expression from Magister Nemo that Satanism is an engineering religion, which to me means that if you feel that the aestethics of norse mythology and the history of the vikings works for you, then you should apply it. Make your own total environment, drink mead, eat roast pork, sing songs in ancient tongues
I don't think I've heard the expression "practicing Satanist" before. Your use of that, as well as "kosher" suggests that perhaps you are still thinking along the lines of the judeo-christian religions. If you find that your interest leads you to commit any Satanic sins or question the basic tenets of Satanism you should use your own judgement as to whether this was a mistake that needed to be corrected or a realisation that you are something else than a Satanist.